Showing posts with label evolution. Show all posts
Showing posts with label evolution. Show all posts

How to Install Variable Length Pushrods in a Harley Davidson Evolution Engine

Thursday, May 22, 2014 | Labels: , , , , , , , , , , , | 1 comments |
How to Install Variable Length Pushrods in a Harley-Davidson Evolution Engine

Pushrods are the longest and most visible pieces in a chain of mechanical components that connect a cam shaft inside a Harley-Davidson Evolution engine, with the rockers that open and close the exhaust and intake valves in a Harley cylinder head. The "lift" of these valves determines how much air and exhaust enters and leaves the cylinders. Within this chain of components, pushrods or rockers may be adjusted. It is easier to adjust pushrods than it is to pull apart the top of the engine. Harleys are shipped with non-adjustable pushrods, but the motor company does sell a set of quick install adjustable pushrods that bolt in as follows.

Instructions

    1

    Shift the motorcycle into top gear. Raise the bike on a motorcycle jack until the rear wheel is completely off the ground.

    2

    Cut the stock pushrods in half with a bolt cutter and pull them off the engine.

    3

    Remove both spark plugs with a spark plug socket and a socket wrench. Shine a flashlight into the front spark plug well and look into it.

    4

    Slowly turn the rear wheel by hand until the front piston is at the top of its stroke.

    5

    Replace the O-rings, the lower pushrod covers and the spring cover keeper with new components supplied in the kit by hand using a flathead screwdriver when needed.

    6

    Loosen the locknut on all of the pushrods with an open end wrench and adjust them to their shortest length.

    7

    Install the pushrods with pushrod covers by hand, ensuring that the adjuster end of the pushrod is down and the ball end of the adjuster is in the tappet socket. Adjust the pushrods for your motorcycle according to the instructions in the kit.

    8

    Lower and remove the motorcycle jack. Replace the sparkplugs with a sparkplug socket and socket wrench.

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How to Change Rocker Box Gaskets on the Harley Evolution

Friday, September 27, 2013 | Labels: , , , , , , , , , | 0 comments |
How to Change Rocker Box Gaskets on the Harley Evolution

The Evolution engine was a significant upgrade over the preceding Shovelhead power plants. Part of the redesign was the replacement of the spade-shaped Shovelhead rocker covers with rocker covers that looked like a stack of blocks. Harley cheerfully nicknamed its new engine the Blockhead. Unfortunately, the Blockheads rocker covers leaked. The covers were redesigned four times. The earliest rocker box gaskets, and the worst, were made of cork -- they were nicknamed "glue and screws." Later generations of these gaskets were made of rubber. Although you can replace these gaskets without pulling off the gas tank, experienced mechanics usually do so.

Instructions

    1

    Park your Harley in a well-ventilated area. Turn the petcock to off. Allow the engine to cool down completely.

    2

    Loosen the fender tab bolt on the back of the seat with an Allen wrench. Remove the bolt and washer. Pull the back of the seat up and back to remove it.

    3

    Disconnect the negative battery cable from its terminal with a box wrench.

    4

    Remove the console bracket bolt or bolts. Use a box wrench on consoles attached to the bracket with a single acorn bolt. Use an Allen wrench on consoles attached to the bracket with two or three Allen bolts.

    5

    Loosen the worm clamp that connects the fuel line to the petcock with a flat-head screwdriver. Remove the fuel line from the petcock.

    6

    Drain your fuel tank through your petcock into a large gasoline storage can. If you have a split gas tank, you must also disconnect the crossover hose and the fuel venting hoses on the bottom of the tanks.

    7

    Remove the front and rear mounting bolts, washers and nuts, using a box wrench on the nuts and a socket wrench on the bolt heads.

    8

    Unplug the fuel gauge connector under the gas tank on later Evolution models.

    9

    Lift the tank straight up and off the motorcycle and set it aside.

    10

    Remove the Allen bolts that fasten the rocker cover to the engine. Remove the cover. Work on one rocker cover at a time, beginning with the front cover.

    11

    Remove the metal gasket, which is called an inner rocker cover or a D-ring. Remove the old gasket. Some gaskets will need to be scraped off.

    12

    Examine the used gasket and rocker housing. Gaskets for housings with only a partial shelf gasket use adhesive. Housings with a shelf to fully support the gasket do not need adhesive.

    13

    Position the gasket on the rocker arm assembly using adhesive if needed. Replace the thin metal inner rocker cover and the rocker cover.

    14

    Replace and tighten the rocker cover bolts according to the specifications in the shop manual for your Evolution. Generally, these bolts are tightened to about 10 foot-pounds of torque.

    15

    Replace the gas tank and reattach the pigtail connection for the fuel gauge. Reconnect the fuel line to the petcock using a worm clamp and flat-head screwdriver.

    16

    Reattach the console to the console bracket. Refill the gas tank. Reconnect the battery cable and replace the seat.

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